✅ EASY TO READ COLOR CHART - From red to green, the large color chart makes distinguishing your test results effortless. The total hardness is measured in both 0-25 GPG and 0-425 PPM, making it a perfect tool to calibrate your water softener or simply check the water hardness. | ✅ QUICK AND ACCURATE - Save time and get the test results within seconds. No need to visit a hardware store or wait for someone else to check the quality of your water. The reliable and consistent accuracy of these test strips provide a simple and convenient way to measure water hardness. | ✅ EASY TO USE - Simple and clear instructions make these hassle-free test strips super easy to use. You don’t need to mess with a complicated test kit to reliably check the hardness of your water. Simply dip the strip into the water and compare it with a large color chart on the bottle. | ✅ EXCELLENT VALUE - 50 high-quality test strips provide a cost-effective way to regularly test your water softener, aquarium, pool and spa water. Even better, the unused strips remain airtight and dry for future use, allowing you to carry out measurements up to 10 months after initial use. | ✅ DEDICATED TEAM OF EXPERTS - You can always count on our team of EPA experts, with more than 30 years of expertise in the water quality industry. That’s why we are single-mindedly devoted to helping you with any questions you may have about water quality testing or the test strips.